Antiretroviral therapy (ART) prevents HIV morbidity, mortality and transmission. When ART is used, the life expectancy of HIV-positive persons in Africa is comparable to that of HIV-negative persons. However, HIV- associated mortality continues to be high, particularly among hard to reach populations such as men. Of the 2.6 million South Africans on ART only a third are men, despite men making up 45% of HIV-positive persons. HIV-positive men are underrepresented throughout the HIV prevention and care continuum, being less likely to test, link to care, initiate ART, and more likely to be lost to folow-up. Few strategies have focused on men, and when they have they have not been successful. We were able to achieve 60% linkage to HIV clinics through an optimized package of HIV testing, point-of-care CD4 testing and lay-counselor support but innovative strategies are needed to motivate HIV-positive men to initiate and adhere to ART. Conditional lottery incentive strategies are an innovative, high-yield strategy for HIV prevention. A recent example of an effective intervention used a lottery incentive (a cash prize of $50 or $100) conditioned on being STI negative, which decreased HIV incidence by 60% among 'risk-loving' individuals in Lesotho; demonstrating one of the largest effects to date of a behavioral intervention for HIV prevention. Men are consistently and significantly more risk-loving that women, and lotteries appeal to those willing to take risks. Because men who drop HIV care are gambling that their health will not be affected by the choice, strategies that involve a gamble may re-engage them in care; analogous to lotteries for HIV prevention. For HIV-positive, ART eligible men conditional lottery incentives have the potential to overcome both structural and behavioral barriers to linking to care, such as logistic barriers and differences in risk perception compared to women. We propose to assess feasibility, test the effectiveness and plan implementation of conditional lottery incentive linkag strategies to engage men in HIV care and ART in KwaZulu-Natal, South Africa (the Lottery to Link Study). Through a participatory implementation process we will engage stakeholders (including clients, providers and Department of Health leaders) to assess the feasibility of conditional lottery incentives. To test the intervention, 120 HIV-positive men will be randomized to an optimized linkage package alone or an optimized linkage package plus a conditional lottery incentive. The proportion of HIV-positive men virally suppressed and engaged in care will be assessed at six months. To plan implementation and operational practices, we will assess the incremental cost of the intervention and explore the use of routinely collected data (on missed clinic visits and missed ART refills) to identify men at risk for loss to follow-up. Our hypothesis is that conditional lottery incentives, above and beyond an optimized linkage package, will successfully reach men and markedly increase engagement in HIV care and viral suppression.